This core will provide resources to address nutritional and behavioral issues relevant in this program project. The studies involved in this program project will focus on several specific nutrients. Because of the interactions of other dietary factors with these nutrients it is important to assess overall dietary quality and to monitor for confounding or interacting nutrients. The related behavioral issues -- particularly adherence, will need to be assessed and intervened on in each clinical trial. Thus, the Core is divided into two main components: Nutrition and Adherence. Each component has specific aims that are independent, but require close collaboration in order to most efficiently act as a shared resource to the program project. Regular monthly meetings of all Nutrition and Adherence Core staff will be conducted in order to assure close monitoring and collaboration on issues that affect the Core goals as a whole. Aims of the nutrition component include: I)supervise design and collection of dietary data; 2) maintain and develop of appropriate food composition data bases; 3) reduce dietary data; 4) provide reduced data to project investigators; 5) consult with project investigators regarding interpretation-of dietary results; and 6) maintain quality control procedures for data collection, coding and analysis. The aims of the adherence component include: I) promote adherence with trial regimens; 2) consult with and provide information applicable to recruitment and retention of subjects to project investigators; 3) identify behavioral, situational and attitudinal factors associated with recruitment, attrition and adherence at various phases in each trial; and 4) test the effectiveness of adherence interventions in each study. Specific recruitment, adherence promotion and attrition prevention strategies will be generated and shared with each of the clinical trials through the adherence component of this core.